Electrical heating unit for tanks



Dec. 10, 1929. 1 HENRY 1,739,030

ELECTRICAL HEATING UNIT FOR TANKS Filed Oct. 21. 1926 INVENTOR. Arfhur J. Henry BY W W/MM A T TORNEYS.

Patented Dec. 10, 1929 UNITED STATES,

PATENT OFFICE ARTHUR J'. HENRY, OF LOS ANGELES, CALIFORNIA, ASSIGNOR 0F ONE-HALF TO SIDNEY J. BUSH, 015 LOS ANGELES, CALIFORNIA ELECTRICAL HEATING UNIT ron TAnKs Application filed October 21, 11926. Serial No. 143,053.

This invention relates to a heating unit for water heaters of the tank type. A. success ful and efiicient type of heater for such tanks comprises spaced electrodes which are arranged to be immersed in the water so as to heat the latter by reason of the electrical resistance of the Water. Such heaters have their electrodes insulated from the tank. Heretofore, the electrodes have been mounted upon rubber supports. These supports lack sufficient rigidity so that a pulsating or alternating current will cause a vibration of the electrodes, the latter moving to and from each other. This causes fluctuation of the electrical current. Expansion and contraction of the supports and mountings for the electrodes, results in a movement of the latter to and from each other so as to cause a difference in the resistance between the electrodes at the different temperatures.

It is the primary object of this invention to provide a unit for mounting at the lower head of the tank, the unit having a base which will close a hand hole in the tank head, and will rigidly support the electrodes at the same time insulating them from the base. In ad dition to the broader objects of this invention, there are certain details of structure, whereby a compact, economical, durable and efiicient structure is obtained.

These objects together with other objects and corresponding accomplishments are obtained by means of the embodiment of my invention illustrated in the accompanying drawing in which:

Fig. 1 is an axial section through a tank with the heater unit embodying my invention mounted therein, a portion of the structure for effecting circulation being shown in elevation; Fig. 2 is an axial section on an en larged scale through a. fragment of the heater unit and the tank; and Fig. 3 is a bottom plan view of the structure shownin Fig. 2,

one of the posts being shown in section; Fig.

4 is a fragmentary plan view showing the details of the bracket and post mounting for the electrodes.

Referring with more particularity to the drawing, 5 indicates a cylindrical iron tank closed at the upper end by a head 6, and at the lower end by a head 7 having a hand hole 8 therein. A collar 9 bordering the hand hole is welded to the outside of the head 7 The collar 9 has bolt holes which are tapped.

The heater unit comprises a base 10 in the form of a disc and preferably made of copper or like metal. The central portion of the base is thickened as indicated by 11 and is formed with apertures 12 which are counterbored at the top and bottom. Disposed in the apertures are mica washers 13, forming in efi'ect an insulator liner for each aperture. Extending through the bores of the washers are posts 14: preferably of copper being threaded to receive nuts 15 and having heads 16. Mounted on the heads of the posts are L shape-brackets '17 having'feet formed with slots 18 to receive scrcws'19. The screws are mounted in threaded apertures in the heads and serve to secure the brackets to the heads. Carbon electrodes 20 are secured to the upright legs of the brackets. The screws and brackets serve for adjusting the distance between the carbons to accommodate the heater collar and the disc to provide a leak tight fit.

Binding post screws 23 are mounted in the lower ends of the post to serve for connecting the terminals of the conductors supplying current thereto.

Obviously, the heater unit may have its elements assembled and then may be secured to the head so as to close the hand hole. The construction is such that the unit is easily removed for attention or replacement. The carbons are rigidly mounted so that they cannot sway or vibrate and are thoroughly in sulated from the disc.

I have provided a novel circulation element for mounting within the tank and over the carbons. This element comprises a cylinder 24 closed at the top and secured to the head at the bottom. There are ports or openings 25 to permit the entrance of water into the lower part of the cylinder. Extending from the top of the cylinder and communicafl ing therewith are pipes 26 extending part way to the to of the tank and opening thereto. Pipes 2? of greater length are also mounted on the head and extend to a point adjacent to the head 6. This circulation device provides for even distribution of hot water throughout the tank.

What I claim is:

1. An electrical heating unit for liquid comprising a rigid base plate of material impermeable to water adapted to close a hand hole in a heater tank, conductor posts rigidly secured therein and extending through said plate, said posts having heads, metallic brackets having lateral arms with elongated slots, screws extending through said slots into said heads so as to provide for spaced adjustment of said brackets, and carbon electrodes fixed to the upstanding arms of said bracket.

2. An electrical heating unit for liquid comprising a metallic base plate having spaced post receiving apertures, said plate being adapted to close a hand opening in a heater tank, mica washers disposed in said apertures, conductor posts having heads disposed above said plate and shanks extending through the holes in said washers to provide mountings for brackets, there being screw holes in the heads of said posts, conductor brackets mounted on said posts, there being an elongated slot in an arm of each of said brackets for registration with a screw hole, screws extending through said slots into said holes for adjustably securing said brackets to said posts, and carbon electrodes secured to the upright arms of said posts.

In witness that I claim the foregoing 1 have hereunto subscribed my name this 5th day of October, 1926. i v I ARTHUR J. HENRY. 

